INVESTIGATION INTO THE DETECTION OF CHLORINE SPECIES BY RHODAMINE 6G CHEMILUMINESCENCE WITH ELECTROCHEMICAL MODIFICATION

A flow system for the determination of free chlorine by a chemilumines cence reaction with Rhodamine 6G in aqueous solution is described. The system was optimized such that a detection limit (signal-to-noise rat io = 3) of 90 mu g l(-1) was obtained for free chlorine. The system wa s found to detect bound available chlorine in water by electrochemilum inescence under the same conditions, but in the presence of a charged electrode. In principle, this system could be used to monitor both fre e chlorine and total available chlorine by switching the electrode vol tage. The mechanism of the chemiluminescence is discussed with referen ce to the analytical advantages of linear calibrations.